Strain-enhanced dynamic regulation of chiroptical responses in 3D suspended nested metamaterials

Area of Science:

• Photonics and Materials Science
• Nanotechnology and Optics

Background:

• Three-dimensional (3D) chiral metamaterials are crucial for advanced photonic devices and spectroscopy due to their strong chiroptical responses.
• Current fabrication methods lack speed, simplicity, and dynamic tunability for 3D chiral nanostructures.

Purpose of the Study:

• To develop a novel, strain-enhanced strategy for the rapid fabrication and dynamic regulation of 3D chiral metamaterials.
• To investigate the relationship between applied strain and the resulting chiroptical properties.

Main Methods:

• A strain-enhanced strategy was employed to transform 2D precursors into 3D suspended nested metamaterials.
• Buckling strain self-assembly was optimized using local strain enhancement for improved precision.
• Morphological changes and circular dichroism (CD) were analyzed under varying substrate pre-strain (ɛpre).

Main Results:

• The study demonstrated dynamic regulation of chiroptical responses in 3D nanopyramids by controlling substrate pre-strain.
• Uplifted heights of nanostructures increased with substrate pre-strain, leading to enhanced CD values up to 0.79.
• The observed CD was primarily attributed to ring electric dipole resonances.

Conclusions:

• The proposed strain-enhanced strategy offers a new pathway for fabricating high-performance 3D chiral metamaterials with tunable chiroptical properties.
• This method overcomes limitations in strain application and precision in self-assembly processes.
• Potential applications include circularly polarized light detection, super-chiral light sources, and advanced nanophotonic systems.